A great variety of forks, slings and grapples have been developed in response to the varied and changing needs for equipment suited to the lifting, moving and supporting of heavy or bulky loads. A continuing problem relates to the handling of heavy loads whose bulk generally requires balancing as well as lifting. In one aspect of this problem, fork lift assemblies have been devised, as described in U.S. Pat. No. 3,863,971, which provide for a movable point of support capable of improving the balance of the load. In another aspect of this problem, reel lifting assemblies have been devised, as described in U.S. Pat. No. 3,549,190, which provide a series of spacer lugs along a spreader bar for roughly adjusting the positions of the lifting chains to bring the center of gravity of the reel into a generally balanced relationship with the spreader bar. Other lifting devices for reels are described in U.S. Pat. Nos. 3,343,861 and 3,583,753, respectively.
There remains a need for a lifting and positioning materials handling device for use with irregular or unbalanced loads where such loads must be balanced prior to their delivery to a work location or to a storage system. For example, telephone cable reels are periodically becoming larger in diameter, longer in axial dimensions, and much heavier in load. Additionally, recent developments in cable reel techniques have led to a preference for irregularly loaded reels.